American cities are becoming less toxic

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American cities are becoming much less toxic, according to a new report from the Environmental Protection Agency.

Levels of several major toxins, including benzene and mercury, have fallen significantly since the Clean Air Act Amendments of 1990, the EPA's Urban Air Toxics Report showed. These reductions include a 66 percent fall in benzene, and a nearly 60 percent drop in mercury from man-made sources.

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Lead in cities' outdoor air, a known developmental hazard for children, has also decreased 84 percent since 1990, the EPA said.

"This report gives everyone fighting for clean air a lot to be proud of because for more than 40 years we have been protecting Americanspreventing illness and improving our quality of life by cutting air pollutionall while the economy has more than tripled," EPA Administrator Gina McCarthy said in a press release.

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The EPA said in Thursday's announcement that its recent actions, including the 2011 Mercury and Air Toxics Standards, will do even more to improve America's air quality